The present invention is directed to a unique fan coil block that may be used in a unique grid configuration system.
The key to building construction today is both economy and flexibility. Many systems for air handling, electrical, plumbing, and other construction systems have been developed that are economical because they can be produced and installed inexpensively. Because the systems are used for many different types of buildings, it is imperative that the systems be extremely flexible.
One example of a system that has been adopted by the construction industry is the use of an overhead grid array system 20 such as that shown in FIG. 1. The grid array system 20 may be used to support overhead devices such as fan filter units, air filters, light fixtures, sprinkler systems, smoke detectors, electrical wiring, and other overhead structure and devices. In one preferred embodiment, the grid array system 20 is constructed from a plurality of supporting elements, rails, or beams (hereinafter “supporting elements 22”). The supporting elements 22 intersect or pass near each other to form grid units 24 that are the open spaces between the supporting elements 22. Overhead devices are supported within the grid units 24. There are many different types of grid array systems 20 and many different sizes of grid units 24 (for example, 2′×4′ or 4′×4′). Most grid array systems 20 use a single size grid unit 24 and repeat the pattern throughout the entire building 66. It should be noted, however, that the sizes of the grid unit 24 could be varied, even within a single building or within an individual room of a building.
FIG. 2 shows an exemplary two-sided supporting element 22 of an exemplary generic prior art grid array system 20. In this exemplary embodiment, at least two sides of each grid unit 24 preferably have a lip 26 to support an overhead device. The shown two-sided supporting element 22 has a lip 26 on both sides so that it can at least partially support an overhead device on both sides of the supporting element 22. A single-sided supporting element, such as that used on an exterior wall, might only have a single lip. The supporting element 22 of FIG. 2 is a generic supporting element as alternative grid array systems 20 may use alternative structure.
Clean rooms 30 are commonly used in industries such as the electronic, medical, and pharmaceutical industries, to reduce the number of particles in the air to specified limitations. In the most common approach, a layer of flat filters is suspended (sometimes in a grid system) from a room ceiling, with the filters extending over the entire area of the ceiling or a partial area of the ceiling. The air is conducted from a plenum above through the filters into an open space in the room and then returned back to the plenum by way of outlets in the room. The filter elements are normally supported or held in place by supporting elements, such as the supporting elements of a grid array system that engage all or part of the peripheral frame of each filter element.
FIGS. 3 and 4 show fan filter units 40 (a single fan filter unit 40 being outlined in phantom) being used in exemplary prior art air handling systems arranged in the grid array system 20. In the most basic form, a fan filter unit 40 is a combination of a filter 42 and a fan 44. These fan filter units 40 come in many sizes and shapes, but for exemplary purposes, the common 2′×4′ dimension unit will be discussed. These 2′×4′ fan filter units may be arranged in a grid array system 20 in the ceiling of, for example, a clean room 30. The fan 44 of the fan filter unit 40 blows air down through the filter 42 of the fan filter unit 40. Placement of multiple fan filter units 40 in the grid array system 20 provides uniformity of airflow.
To use the systems of FIGS. 3 and 4, the air must be cooled before it reaches the fan filter units 40. As shown in FIG. 3, one way to cool the air being blown by the fan filter units 40 is to provide a remote cooling fan 46 in the plenum 50 above the fan filter units 40. The remote cooling fan 46 cools the air in the plenum 50. The fan filter units 40 then circulate the cool air. As shown in FIG. 4, another way to cool the air being blown by the fan filter units 40 is to provide a cooling coil 52 under the floor 54 of the clean room 30. In known systems, the cooling coil 52 is located near a return air chase 60 in which a return fan 62 directs air back to the plenum 50 above the fan filter units 40. The cooling coil 52 cools the air that is then returned to the plenum 50. The fan filter units 40 then circulate the cool air.
The embodiments of both FIG. 3 and FIG. 4 use an exterior, predetermined return air chase 60. Air flows throughout the rooms 30 in one direction (generally downward) and exits through a perforated floor 54. The air then is driven or pulled to the substantially adjacent return air chase 60. FIG. 1 is a top plan view of an exemplary prior art grid array system 20 in which the exterior return air chase 60 is positioned against the exterior wall 64 of the building 66. The embodiments of FIGS. 3 and 4 could only be implemented for the rooms 30 in the building 66 that have at least one wall adjacent to the return air chase 60. This limitation creates several problems. First, as can be seen from FIG. 1, rooms 30 that are to have airflow such as that shown in FIGS. 3 and 4 must be positioned against the exterior wall 64 of the building 66. This limits the arrangements of rooms within the building. Second, the exterior return air chase 60 is essentially wasted space.
The present invention solves the problems of the known prior art.